Updated bounds on milli-charged particles

Abstract

We update the bounds on fermions with electric charge ∈e and mass m∈. For m∈ ≲ me we find 10-15 ≲ ∈ < 1 is excluded by laboratory experiments, astrophysics and cosmology. For larger masses, the limits are less restrictive and depend on m∈. For milli-charged neutrinos, the limits are stronger, especially if the different flavors mix as suggested by current experimental evidence.